Definition
IO Architecture
The IO architecture is a layered structure organising IO functions by abstraction level. It provides a uniform user interface while managing device-specific operations at lower levels.
Layers
Logical IO
User-level interface providing high-level commands (
open,close,read,write). Treats all devices as logical resources.
Device IO
Translates logical commands into device-specific instructions. Handles buffering.
Scheduling and Control
Manages hardware interaction: IO request queuing, disk scheduling, interrupt handling, device status monitoring.
File System Layers
Directory Management
Maps symbolic file names to unique identifiers; handles directory operations.
File System
Manages logical file structure and access control.
Physical Organisation
Translates logical file references (byte offsets) to physical device locations (track, sector).